Storm-0940 Uses AI Agents to Breach ConnectWise Supply Chain
A China-aligned group leveraged an open-source AI framework to scan thousands of Microsoft 365 tenants, achieving privileged access in under three hours.
By Jayden Sweiler ·
Speed is the new currency in cyberattacks, and a recent breach proves it.
Microsoft revealed that a China-state-aligned hacker group known as Storm-0940 deployed AI agents to execute a large-scale supply chain attack through ConnectWise. The group used ARTEX, an open-source framework for autonomous penetration testing, to automate scanning and reconnaissance. This allowed them to move faster than traditional human-led attacks.
The operation began after the group gained unauthorized access to the multi-tenant ConnectWise application. They then used stolen credentials to authenticate as the app itself, bypassing normal user sign-ins. This technique allowed them to attempt sign-ins at more than 2,250 Microsoft 365 tenants. Some of these attacks reached privileged access levels in less than three hours after the initial targeting.
The attackers also ran automated password spraying campaigns. These efforts targeted 327 accounts across eight organizations. The result was over 151,000 failed logon attempts without a single success. At its peak on October 11, the system made 2,900 attempts per minute. Nearly 98% of this activity was locked out, but the sheer volume overwhelmed standard defenses.
ARTEX works by running LLM-driven agents that operate with little human interaction. This pace leaves defenders with very little time to detect and respond. It is currently unclear how the ConnectWise credentials were originally stolen or exactly how many tenants were fully compromised. However, the activity did not stem from a vulnerability in Microsoft’s own systems.
Storm-0940 has been active since 2021 and targets industries including aerospace, defense, semiconductors, and government think tanks. In one specific incident on October 15, a security firm named Huntress observed an app adding itself to a top administrator role. The attackers also planted new secrets set to expire in 2028. By October 16, the firm confirmed unauthorized sign-ins for 162 tenants. By the next day, that number had grown to almost 1,000 tenants with sign-in activity from the attacking IP.
The attack pattern showed a script working from a sorted target list. Sign-ins occurred just seconds apart across multiple tenants. This differs from traditional attacks because of the use of open-source AI tools. CrowdStrike noted that the suspect in similar attacks on South Korean financial institutions likely used ARTEX with Anthropic’s Claude Code. The developer of ARTEX has since announced the project will become closed source and stop receiving updates.
ConnectWise suspended several services, including Cloud Backup and SaaS Security, as a precaution. A phased restoration has begun, with recovery expected to take several days. The company reports no indicators that partner backup data was compromised. Microsoft advises customers to keep affected app connections disabled until formal restoration instructions are issued. They also recommend reviewing activity logs from this month to assess the full scope of the intrusion.
Source: Tom's Hardware
